Inputs
Enter chords separated by spaces (slash chords like G/B work). The new key sets the shift; output spelling follows the ♯/♭ toggle. Everything is computed in your browser.
Pick the instrument and the concert (sounding) key your part should sound in; it shows the key the player must read. The chart lists all 12 keys. Nothing is uploaded.
Result
- Transpose
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- Capo hint
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- Transpose
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- Interval
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Read-as chart (all 12 keys)
| Concert | Reads |
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A tool for transposing chords and keys. In 'Chord transpose' mode, type chords separated by spaces (C G Am F, slash chords like G/B are fine), pick the original key and the new key, and it transposes every chord using twelve-tone interval math. It shows how many semitones up the transposition is and, for guitar, a capo hint — which fret lets you keep the original chord shapes while sounding in the new key — handy for moving a karaoke or vocal key up or down, or swapping to easier open chords for singing. Output spelling follows a ♯/♭ toggle. In 'Transposing instrument' mode, choose an instrument such as trumpet or clarinet (B♭), alto or baritone sax (E♭), French horn (F), etc., and convert between the concert (sounding) key and the written key the player reads, with the interval (major 2nd, major 6th…) and a full 12-key read-as chart — useful when writing wind-band parts or checking part transpositions. The chart prints straight from the browser. Everything is computed in your browser; the values you enter are never sent to any server or API.
How to use
- Choose 'Chord transpose' or 'Transposing instrument' mode.
- For chords, type the chords and pick the original and new key (toggle ♯/♭ spelling). For instruments, pick the instrument, direction, and the concert or written key.
- Read off the transposed chords with the semitone shift and capo hint, or the converted key and the full 12-key chart (nothing is sent). You can print it too.
FAQ
Are the chords or keys I enter sent anywhere?
No. The transposition is computed entirely in your browser. The chords and keys you enter are never sent to any server or API — everything stays on your device.
Can it transpose slash chords (like G/B) and extended chords?
Yes. It transposes the root and the bass note after the slash, while keeping suffixes such as m7, sus4, maj7 or add9 unchanged. So G/B becomes A/C# and Am7 becomes Bm7 when shifting up a whole step.
How do I know which capo fret to use?
When you transpose up, the number of semitones is the capo fret (e.g. up 2 semitones = capo 2). Keep the original chord shapes, add the capo, and it sounds in the new key. A capo only raises pitch, so to go lower, transpose the chords themselves.
What does 'read-as' mean for transposing instruments?
Instruments such as B♭ (trumpet, clarinet) or E♭ (alto sax) sound a different pitch than what's written. The tool adds or subtracts each instrument's interval to convert between concert and written keys and lists all 12 keys. For example, to sound a concert C on a B♭ trumpet, the player reads a D — a major 2nd higher.
When should I use ♯ versus ♭?
Use the ♯/♭ toggle to choose the output spelling. Sharp keys (G, D, A…) are usually written with sharps, and flat keys (F, B♭, E♭…) with flats. Pick whichever matches the song's key signature.